Beating the summer heat an urgent issue for 2020 Tokyo Olympics

In this May 20, 2017 file photo, pedestrians wait for a traffic signal to change under the shade of a tree in Tokyo's Chuo Ward. (Mainichi)

Tokyo is surging ahead with its planning for the 2020 Olympic and Paralympic Games as it prepares to mark three years before the launch of the games on July 24. However, more thought needs to go into measures to beat the heat -- especially for the marathon and race walking events -- as the games will be held during one of the most oppressively hot times of year.

The women's marathon is set to be held on Aug. 2, 2020, while the men's event will be held on the final day of the games, Aug. 9, with a 7:30 a.m. starting time for both events. However, data from the past 10 years shows that Aug. 9 has an average temperature of roughly 27 degrees Celsius at 7 a.m., while at 10 a.m., two and a half hours after the projected start time, the average temperature is roughly 30 C. Last year it got up to 35.6 C.

To curb rising temperatures on the road surface, the Tokyo Metropolitan Government has introduced pavement with a strong thermal barrier. After coating the asphalt with heat-reflecting materials, a test run was held in August 2016. When compared to regular pavement, the treated asphalt was reportedly 6 degrees cooler. That is a promising result, but it doesn't seem quite enough. Shouldn't officials consider moving up the start time for the events, even if it increases the burden on volunteers and event staff?

In setting rules for outdoor exercise, the Japan Sports Association uses the "Wet Bulb Globe Temperature (WBGT) measurement, which is based on temperature, humidity and environmental factors, like radiation from sunlight. The association suggests not engaging in intense exercise when temperatures rise between 31 and 35 degrees Celsius, and to completely halt exercise in principle when the temperature rises above that range.

In a conference between the metropolitan government, The Tokyo Organising Committee of the Olympic and Paralympic Games and other groups in June, it was confirmed that full-scale surveys of the temperature and humidity around the various event venues would be carried out starting this fiscal year. With such issues as the cost of holding the games and the condition of the venues piling up, officials are finally set to launch full-scale efforts to work out countermeasures to beat the Tokyo summer heat. There are only three more chances to collect data in mid-summer and conduct experiments. Time is running out.

Masaaki Sugita, a professor in the physical education department at Nippon Sport Science University who provides medical support to athletes including members of the Japanese Olympic track-and-field team, says that the main things to keep in mind when protecting athletes against the heat are preventing a rise in body temperature, keeping them hydrated, and providing them with the electrolytes and minerals that their body loses when they sweat. Effective methods for cooling and hydrating the body are being researched all over the world to give athletes the upper hand.

But even then, something like this could happen: During the men's marathon at the 2007 World Championships in Athletics, which was held in Osaka in August, the temperature soared to over 30 degrees Celsius at the beginning of the event at 7 a.m.

Over 30 percent of the 85 runners had to drop out of the race partway through. That is definitely not the sight we want to see in Tokyo in three years' time. (By Takakazu Murata, Tokyo Sports News Department)